1. Field of the Invention
Methods and apparatuses consistent with the present invention relate to calibrating a color property of a monitor, and more particularly, to calibrating a color property of a monitor in such a manner that a color having a color property preset by the user can be output from a monitor.
2. Description of the Related Art
Accuracy and stability are very important factors to be considered when reproducing colors on a color monitor. The term “stable color reproduction” means a color change will not occur on the monitor even if a long time has lapsed. In addition, the term “accurate color reproduction” means an image is reproduced according to color information of the image, which has been input to the monitor. For instance, if the input image is an sRGB image, the monitor must reproduce the image with a color level available from an sRGB standard monitor.
A typical method of ensuring the stability of the monitor is to utilize a color meter called a “calibrator”, which is used in a Barco CRT monitor or an EIZO LCD monitor. The user measures white and black of the monitor by using the calibrator, and then corrects the setting status of the monitor when there is a difference between a measured value and a target value, thereby properly maintaining the monitor. Such a procedure is called a “calibration”.
In order to accurately reproduce color on the monitor, an emulation technique is necessary in order to emulate the color as if the monitor has a virtual primary different from a real primary. This can be achieved by performing color calibration in the monitor. The emulation technique can be performed using numerical formulas when an accurate characterization model exists. However, since there are limitations in the stability of the monitor and the accuracy of the numerical formula model, the calibrator is utilized for accurate emulation. Thus, the performance of the monitor may vary depending on the monitor calibration system and calibration algorithm.
Conventional calibration techniques for a monitor using a light or a color meter are mainly classified into gamma calibration, white calibration, and color coordinate calibration techniques. In addition, a method of measuring luminance has been suggested that creates a look-up table for gamma calibration in each channel or white calibration.
Most of the above techniques are focused on white and gamma calibration. However, in addition to the white and gamma calibration, the emulation technique for the primary coordinates of the primary is also important, and it is impossible to directly utilize the conventional white calibration scheme for the primary calibration.
According to the conventional method, several colors are measured so as to set parameters, and target values are input by a user so as to process the colors. However, according to the conventional method, accuracy of the color conversion is determined according to accuracy of an output color prediction formula prepared based on measurement values of several colors, so the accuracy of the color conversion corresponding to input target values may not be ensured.